Beginner’s guide to planting
Confused by talk of annuals, perennials and biennials? Julia Atkinson-Dunn has the answers.
One of the first barriers I hit when dipping my toe into gardening was the ‘‘lingo’’. I found that gardeners in the ‘‘know’’ would readily answer my questions of ‘‘what, when, how’’, but inadvertently create more blank-faced confusion when using exclusive garden language in their explanations. This created brain explosions and a real barrier to my enthusiasm to even continue learning.
Now I am underway, I understand their need to use gardening terms and their relevance to designing, learning and growing a garden that I would love.
The plant categories below have unlocked my creativity and pathways to further knowledge and I hope they will keep you on track, too. Once you understand about identifying each plant you love as existing in one of these categories, you suddenly are able to plan your garden, understanding your investment in plants and what will return each year. It’s like seasonal decorating of your garden room.
This information is also helpful if you have inherited a garden. Wait a full year to see what ‘‘pops up’’ over the seasons to understand what you are working with and where plants are hiding.
Perennials
These plants recede down to their roots each year, ‘‘re-grow’’ in spring/summer, flower, set seed and repeat for two or more years into the future.
Features of perennials: They are terrific ‘‘investments’’. If you choose to buy established plants instead of growing from seed, you can do so with the knowledge that they will deliver year after year and you will be able to ‘‘divide’’ and create more plants to spread around your garden. Even better is being gifted a division from someone else’s garden.
Some will last for years (and may take a few to get going). Some may be shorter lived and start to tire after three years or so.
My favourite perennials: Verbena bonariensis, Japanese anemones, dahlias, thalictrum, knautia, echinacea, rudbekia, astilbe, delphiniums, irises, salvia, eryngium, astrantia, sanguisorba and hostas.
Tender perennials: These perennials won’t survive their dormant period in very cold climates. Very often plants listed as tender perennials in other climates that are under snow all winter are less fussy here in New Zealand, where we don’t have the same low temperatures for a sustained period of time. This just means they are more likely to survive with us.
Bulbs/corms/tubers/rhizomes: These grow from strange bulbous ‘‘storage organs’’ of differing types. Some are hardy and some tender. Many are also commonly exciting late-winter, early-spring surprises before they wilt away underground again. They will also be multiplying and each year or two are worth digging up once their leaves have died down, to gently divide and replant your new stock elsewhere.
Common bulbs: Daffodils (also known as narcissus/jonquil family), lillies, tulips, amarylis and garlic.
Common corms: Bearded iris, crocus, gladioli, ranunculi.
Common tubers: Dahlias, peonies and potatoes.
Common rhizomes: Anemones, ginger and bamboo.
I’d advise looking up how to plant each type listed above, as I definitely planted my peony tubers upside down and had to dig up and do again.
Shrubs: These perennials are smaller than trees and have woody stems above the ground when dormant. When they are dormant over winter, they can either be evergreen (with leaves all year around, like box hedging, camelias and rhododendrons), or they can be deciduous (where they lose their leaves to reveal their woody stems, like hydrangeas).
Shrubs are important for flower gardens, as they offer structure all year, supporting your little landscape with visual interest when your other plants have finished for the year.
Annuals
These grow, flower, set seed and die in a single year. Often they are prolific self-seeders and will re-emerge as new plants in the same position (or across the garden) the following year.
Advantages of annuals: They are celebrated for their abundant colourful blooms, especially in summer, instantly brightening and cheering up your outside space. I’ve found them to be eager, fast-growing and many will flower for months given good care (watering and deadheading), growing in a position they are happy with.
Many annuals are fantastic for use in hanging planters and pots, as well as planting to add interest to the edges of your garden. You might spot many annuals being referred to at garden centres as ‘‘bedding’’ plants.
My favourite annuals: Cosmos, annual lupins, sunflowers, sweet peas, zinnias, snapdragon, larkspur, nigella, petunias, lobelia, zinnias, fennel and companion-planted marigolds with my veges.
Hardy annuals: These annuals can be sewn directly into the ground where you want them to grow and can tolerate cold and frosts. Often they can be sewn in late-autumn or early-spring.
Half-hardy annuals: Plants that need some more nurturing by planting in seedling containers and in shelter away from frost before transplanting into their garden position once well-established.
Biennials
Unlike annuals, biennials complete their lifecycle over two years. From seed, they establish their roots, stems and leaves in the first year, the second season they flower, set seed then die.
Advantages of biennials: For me, the advantages simply come down to the attractiveness of the plants that fall into this category. My patience was tested with the two-year cycle.
Once you get them in a self-seeding cycle, they’ll be there every year and it will seem as though they are flowering annuals anyway. There is also work by breeders to make many biennials bloom in the first year.
My favourite biennials : Foxgloves (although many are now annual), hollyhocks, queen anne’s lace.
Why is it helpful to understand these terms? I readily move my perennials around to find them better positions for them to perform, but also divide their ‘‘clumps’’ as they grow to gain more plants or share with others. I keep a subtle notebook and brain record of where they are (as they are invisible during winter), which allows me to also make sure I leave space to experiment with fun vibrant annuals each year.
Understanding the slow-going process of biennials means I don’t rush to pluck out a green, but unflowering plant in confusion, now knowing it will deliver me flowers the following year.